When his six-year-old daughter Seren starts talking of a ghostly woman who visits her room each night, young widower John Gimmerick isn't too concerned. After all she already has an imaginary friend. But when his own nightmares begin to merge with reality and when unexplainable things start to happen around the house, John realises that by revisiting the home of his childhood he's stirred up things he'd tried hard to forget - as well as something that should never have been stirred in the first place. Now, in order to save his little girl from an evil that speaks only of death, reclusive John must face up to the horrors of his past. And what he discovers runs deeper and is far more terrifying than he could ever have imagined...